Make a Connection Study after study has shown that people who feel lonely, depressed and isolated are three to five times more likely to get sick and die prematurely—not only from heart disease, but from all causes—than those who have feelings of love, connection and community. In one study of heart attack survivors, those suffering from depression were five times more likely to die within six months than the subjects who were not depressed, similar to what we have found in our own patients.

You can start by speaking with one stranger per day. Call one old friend per week. Join a support group like Overeaters Anonymous or a quit-smoking club, or organize some friends to meet regularly and cheer one another on. Learn some communication skills. Get a massage, manicure or shampoo, and give someone a hug when she's done a good job—or even when she hasn't. There are dozens of studies demonstrating the healing value of touch.

Altruism, compassion and service also protect the heart. Find one charitable endeavor per season. We are hard-wired to support each other—the trait has helped us survive as a species for the past several hundred thousand years. If none of these efforts help, talk to a doctor or therapist.

Have a Helping of Attitude People who are "glass half-full" types may not need another reason to be positive, but the latest studies show that those of us with a more optimistic view of the world tend to live longer and have fewer heart attacks. The good news for the "half-empties": Optimism can be learned.

Appreciation of others and of yourself is strongly correlated with happiness and health. Nobody lives forever, so you might as well try to get the most fun and enjoyment out of life for as long as it lasts. The choices you make each day—in terms of your diet, exercise, attitude and behavior toward others—are much more powerful determinants of your health than anything we or any other doctor can provide. As one of our patients once told us, "Now that I'm making these changes, not only are my arteries more open, but I'm more open." A little love and appreciation, when all is said and done, may be the heart's best medicine.